DE10348551A1 - Electronic control device for use in motor vehicles and domestic appliances has separate ground structures for voltage regulator and other electronic circuits - Google Patents

Abstract

A control device (1) supplied from an external supply (7). It has an internal voltage regulating circuit (2) and a microcomputer to issue commands based on inputs (4) from external sensors. The device is formed on a multilayer substrate (15) and has two ground structures. One (20) is provided for the voltage regulating circuit components (22,23,25) and it is connected (32) to a second (30) forming a common ground for the remaining electronic components.

Description

The present invention relates an electronic control device with a current or Power supply circuit for setting an externally applied Supply voltage.

A power supply circuit that outputs a voltage that is set to a desired level by switching regulation has been introduced as a power supply circuit for an electronic control device. An example of such a power supply circuit is shown in FIG JP-A9-37545 presented and in 8th shown. A control circuit is with a base of an output transistor 101 connected to the input terminal of which a voltage is applied.

The control circuit 105 generates square wave duty signals or square wave duty signals SD, which in 9 are shown for switching the output transistor 101 , and generates a duty cycle related to switching according to a desired output voltage level. An output terminal of the output transistor 101 is connected to a smoothing circuit consisting of a capacitor 102 and a choke coil 107 is formed. A diode 106 is connected in parallel to the smoothing circuit.

If the output transistor 101 from the control circuit 105 is turned on, a current flows, which in 8th is indicated by an arrow A '. As a result, the choke coil 107 excited and the capacitor 102 loaded. If the output transistor 101 is switched off, which generates in the choke coil 107 stored energy a current flow, which in 8th is indicated by an arrow B '. In other words, the current flows in a closed circuit, which is a free-wheeling diode 106 who have favourited Choke Coil 107 and the capacitor 102 contains.

The condenser 102 carries supply voltages regardless of the on / off state of the output transistor 101 to. Because a charge current is greater than a discharge current when the output transistor 101 is switched on, a connection voltage Vc of the capacitor increases 102 , The connection voltage Vc of the capacitor 102 decreases when the output transistor 101 is turned off. The relationship between the terminal voltage Vc and the on / off state of the output transistor 101 is in 9 shown.

The control circuit 105 monitors the supply voltage Vc and sets the duty cycle of the output transistor 101 such that the terminal voltage Vc remains within a predetermined range. With these operations, a DC voltage can be output from the power supply circuit at a desired voltage level.

Over the past few years electronic control devices for electronically controlled vehicles or for domestic appliances complex and the scope of the devices Circuits increased. To the size of one Decreasing substrate has become predominantly a multilayer Substrate as a substrate for electronic control devices used.

The substrate has an inner layer with a common ground wiring structure for a different electronic circuit. Ground connections of the electronic circuit are connected to the common structure. If ground connections of the smoothing circuit and in 8th shown diode 106 connected to the common structure, a large current flows repeatedly as indicated by the arrow A 'or B' according to the switching operation.

when the large current from the ground terminal of the smoothing circuit and the diode 106 flows, voltages at the connection points change due to the impedance of the common structure. When an analog-to-digital converter using a ground potential of the common structure is connected to the ground structure, an analog-to-digital conversion cannot be performed with high accuracy.

Object of the present invention is therefore to create an electronic control device at what voltages on the common wiring structure don't change even then if a multi-layer substrate is used.

The task is solved by the features of claim 1.

An electronic control device of the present invention a current or voltage supply circuit for setting a from the outside applied supply voltage to a desired level. The power supply circuit is formed on a multi-layer substrate.

The power supply circuit contains a switching component and an output voltage generating circuit. The supply voltage becomes an input port of Switching component created by a touch or

Clock signal (duty signal) driven becomes. The output voltage generating circuit generates an output voltage which is formed from a voltage generated by the switching device is entered.

The power supply circuit further includes a ground wiring structure, a common ground wiring structure and a connector. That of the output voltage generating circuit associated ground wiring structure is with the output voltage generating circuit connected and defines an electrical ground potential of the output voltage generating circuit. The for all electronic contained in the electronic control device Common ground wiring structure provided by circuits is formed in a multi-layer substrate and defines one electrical ground potential of each electronic circuit. The Connection part is for connecting the ground wiring structure to the common ground wiring structure provided.

If the switching component of that Clock signal is driven, a large current from the output voltage generating circuit led to the ground wiring structure, the common ground wiring structure unaffected becomes. Even if a circuit which has a ground potential the common ground wiring structure works, connected to the structure the circuit operates with high accuracy.

The present invention is disclosed in the following description with reference to the drawing explained.

1 Fig. 12 shows a block diagram of an electronic control device of the first embodiment of the present invention;

2 FIG. 12 is a circuit diagram of a driving section of a current included in the electronic control device of the first embodiment. Power supply circuit;

3 Fig. 14 is a cross sectional view of a multi-layer substrate included in the electronic control device of the first embodiment;

4A Fig. 13 is an explanatory diagram of a driving section showing a current flow in the case that a switching component of the first embodiment is turned on;

4B Fig. 14 is an explanatory diagram of a driving section showing a current flow in the case that the switching component of the first embodiment is on;

5 Fig. 11 is a timing chart showing voltage changes at connection points between a ground wiring structure and capacitors or a free-wheeling diode in the event that the switching component of the first embodiment is on or off;

6 Fig. 12 is a cross sectional view of an electronic control device of a modification of the first embodiment;

7 Fig. 14 shows a cross-sectional view of an electronic control device of another modification of the first embodiment;

8th shows a circuit diagram of a power supply circuit according to the prior art; and

9 shows a graph showing the output voltage of the in 8th illustrated power supply circuit according to the prior art.

The preferred embodiments of the present invention will be made with reference to the figures explained. In terms of of the figures the same reference numerals for the same components and Circuits used.

First embodiment

Corresponding 1 contains an electronic control device 1 a current or voltage supply circuit 2 , a microcomputer (MC) 3 , an input circuit 4 and a drive circuit 5 , The electronic control device 1 sets an externally applied supply voltage to a desired level. The power supply attitude 2 the set voltage leads the internal circuits including the MC 3 , the input circuit 4 and the drive circuit 5 to.

The input circuit 4 filters the signals entered by various sensors. The from the input circuit 4 processed signals are from one in the MC 3 contained analog / digital converter from an analog signal to a digital signal. The MC 3 performs operations based on the digital signals and determines control values for driving various electronic loads according to the results of the operations. Control signals, which indicate the control values, are sent to the control circuit 5 entered, and there are the electronic loads from the control circuit 5 driven.

The power supply circuit 2 has a control section 2a and a drive section 2 B , Corresponding 2 gives the control section 2a a duty signal a gate of the switching component (N-channel power MOSFET) 29 in the control section 2 B for driving the MOSFET 29 by the tactile signal. In particular, the control section generates 2a a square wave signal (clock signal) and sets a duty ratio of the square wave signal based on a desired voltage.

The control section 2 B has an input-side smoothing circuit, which with an input terminal of the power supply circuit 2 connected is. The input side smoothing circuit is from a choke coil 21 and a capacitor 22 educated. It smoothes the supply voltage from an external power supply 7 is fed. The smoothed supply voltage charges the capacitor 22 , With this operation there is a constant voltage from the capacitor 22 the MOSFET 29 even if the supply voltage is currently changing. In addition, the other connection is the capacitor 22 with a ground wiring structure 20 at a ground point 26 connected.

A connection voltage of the capacitor 22 is on a drain of the MOSFET 29 created. A source of the MOSFET 29 , which is an output terminal, is connected to an output-side smoothing circuit. The smoothing circuit on the output side is made of a choke coil 24 and a capacitor 25 educated. A free-wheeling diode 23 is connected in parallel with the output-side smoothing circuit and, together with the smoothing circuit, forms an output voltage generating circuit. One of the capacitor's connections 25 is with the mass structure 20 at a connection point 28 connected. An anode of the freewheeling diode 23 is with the mass structure 20 at a ground point 27 connected.

With the above structure, the power supply circuit gives 2 a desired DC voltage when the MOSFET is driven by the key signal.

Corresponding 3 contains a multi-layer substrate 12 various components and electronic parts attached to a surface of one of its layers. An electrode one in the input circuit 4 contained filter capacitor 4a is on a pad structure on an upper layer surface of the multilayer substrate 15 formed wiring structure 31 soldered. Similarly, an LSI of the MC 3 are the capacitors 22 . 25 and the freewheeling diode 23 with the wiring structure 31 connected.

The top or top layer contains a common ground wiring structure 30 which electronic components, parts and circuits provide a ground potential. An inner layer of the multilayer substrate 15 also contains electronic components, parts and circuits, the wiring structure 31 and the common ground wiring structure 30 ,

Furthermore, one is the control section 2 B assigned ground wiring structure 20 formed on the top layer. In other words, capacitors' ground connections 22 . 23 and the freewheeling diode 23 are with the ground wiring structure 20 at their respective earth points 26 . 27 . 28 connected. The ground wiring structure 20 is with the common mass structure 30 via an interlayer connection part 32 connected, which is formed in a contact tube.

The multi-layer substrate 15 is formed from layers of glass epoxy resin for an insulator and copper foil for wiring structures, which are placed alternately. A multilayer ceramic substrate can be used for the multilayer substrate 15 be used. A thermoplastic resin can be used for the insulator.

For connecting the mass structures 20 and 30 A contact hole drilled with laser light can be used via the interlayer connection. Copper is applied within the contact hole by means of electroplating (plating). The wiring structures 20 and 30 , which are formed in different layers, can be electrically connected at a desired point through the contact hole. The inside of the contact hole can be conductive by filling in a conductive paste.

With the power supply circuit 2 becomes the MOSFET 29 controlled by a key signal for generating a DC voltage by setting the supply voltage to a desired level. When the MOSFET is turned on by the key signal, the generated in the capacitor 23 accumulated electrical charge is a current that flows through the choke coil 24 to the capacitor 25 flees. The current flows in a closed circuit which comprises the smoothing circuit on the input side, the smoothing circuit on the output side and the ground structure 20 like an arrow from a dotted line in 4A displayed.

The moment the MOSFET is turned on, the current begins to flow at a burst, which is caused by those in the capacitor 22 accumulated electrical charge is generated. As a result, large currents flow in the input smoothing circuit and the output smoothing circuit. Furthermore, the current in the output smoothing circuit changes considerably. Therefore, the electrical potential of the mass structure changes 20 at the ground point 28 of the capacitor 25 the moment when the MOSFET 29 as in 5 shown is switched on. This is because the mass structure 20 has an impedance which contains a resistance component. Although in 5 a large current from the capacitor is also not shown 22 fed. This changes the electrical potential of the ground structure 20 at the ground point 26 light.

When the MOSFET is switched off, it moves in the choke coil 24 accumulated electrical charge continues to produce a current which flows in a closed circuit as indicated by an arrow shown by a dotted line. The closed circuit contains the freewheeling diode 23 who have favourited Choke Coil 24 , a capacitor 25 and the mass structure 20 , The moment when the current from the electric charge in the choke coil 24 generated, flows in great current. Therefore, the electrical potentials of the ground structure change at the ground points 28 and 29 ,

If there is an electrical potential of the common ground structure 30 changes, the operation or Operating accuracy of the A / D converter 6 , since it is related to the ground potential of the ground structure 30 is working. Therefore, the electronic control device 1 with the mass structure 20 which the control section 2 B is assigned in addition to the common mass structure 30 Mistake. This reduces an effect of the potential change at the mass points 26 . 27 . 28 on the common mass structure 30 ,

The circuit is designed so that the through the ground structure 20 which between the mass points 26 . 27 . 28 is located, generated impedance Zp1, Zp2 is smaller than the impedance Zv of the interlayer connection part 32 is. Because the mass structure 20 defines the ground potential, it is formed in a relatively large area. That for connecting the mass structure 20 and the common mass structure 30 provided interlayer connection part 32 is made of a conductive material formed in the contact hole with a small diameter. Therefore, the interlayer connection part forms 32 a greater impedance than the ground structure 20 , Even if the potential change in the mass structure 20 occurs, most of the current flows to the closed circuit as indicated by the arrow A or B in FIG B displayed. This reduces the effect of the change in potential on the common mass structure 30 ,

The control section 2 B assigned mass structure 20 is on the top surface of the multilayer substrate 15 educated. This leaves the wiring of the capacitors 22 . 25 and the freewheeling diode 23 for a connection to the ground structure 20 short, and an increase in impedance due to wiring can be reduced. This increases the current flow from the drive section 2 B to the mass structure 20 when the MOSFET is driven by the key signal.

Modifications to the First Embodiment Correspondingly 6 is the drive section 2 B assigned ground wiring structure 20A in the inner layer of the multilayer substrate 15 educated. The ground connections of the capacitors 22 . 25 and the freewheeling diode 23 are connected to a pad structure formed in the upper layer. The pad structure is via an interlayer connection part 32A to the mass structure 20A connected. The control section 2 B assigned mass structure 20A and the common mass structure 30 are provided separately. Thus, substantially the same effect as that of the first embodiment can be obtained.

It is advantageous if the mass structure 20A as close as possible to the layer in which the power supply circuit 2 is formed, is formed to the impedance between the drive section 2 B and the mass structure 20A to reduce. A ground connection of an electronic component 35 , which is not affected by the change in ground potential, is due to both the ground structure 20A as well as the common mass structure 30 via a via 40 as in 7 shown connected. A conductive material is in the via 40 intended. As a result, the mass structure 20A and the common mass structure 30 via the ground connection of the component 35 electrically connected to each other.

The present invention should not to the one discussed above and be limited to the embodiment shown in the figures, but can be in various ways without departing from the scope of the invention be implemented. For example, with regard to the input side smoothing circuit not be necessary for a Wiring distance between the power source and the electronic rule Control device is short or one against noise or interference such as Radio sensitive device is not placed in the input path is.

The power supply circuit can as a power supply circuit of a step-up type or structured as a power supply circuit of a reverse type be as long as a switching operation, from a switching component carried out becomes. It can a MOSFET or other components are used, which as Work freewheel component.

An electronic control device has been disclosed above. The electronic control device ( 1 ) contains a power supply circuit ( 2 ), electronic circuits, a ground wiring structure ( 20 ) and one in a multi-layer substrate ( 15 ) formed common, ground wiring structure ( 30 ). The ground wiring structure ( 20 ) is the power supply circuit ( 2 ) and the common ground wiring structure ( 30 ) is intended for all electronic circuits. Even if an electrical potential of the ground wiring structure ( 20 ) due to a switching operation of one in the power supply circuit ( 2 ) contained switching component ( 29 ) changes, the common ground wiring structure ( 30 ) unaffected.

Claims (9)

Electronic control device ( 1 ) with a on a multilayer substrate ( 15 ) formed power supply circuit ( 2 ) for setting an external power supply ( 7 ) supplied supply voltage to a desired level, the power supply circuit ( 2 ) contains a switching component, which is the supply voltage is applied to the input terminal thereof and which is driven by a key signal, and an output voltage generating circuit ( 23 . 24 . 25 ) for generating an output voltage, which from a switching device ( 29 ) input voltage is formed with: a ground wiring structure ( 20 ) which the output voltage generating circuit ( 23 . 24 . 25 ) assigned; a common ground wiring structure ( 30 ) for everyone in the electronic control device ( 1 ) contained electronic circuits; a connecting part ( 32 ), the ground wiring structure ( 20 ) with the output voltage generating circuit ( 23 . 24 . 25 ) is connected and an electrical ground potential of the output voltage generating circuit ( 23 . 24 . 25 ) defines the common ground wiring structure ( 30 ) in a multi-layer substrate ( 15 ) is formed and defines an electrical ground potential for each electronic circuit, and the connecting part ( 32 ) for connecting the ground wiring structure ( 20 ) with the common ground wiring structure ( 30 ) is provided. Electronic control device ( 1 ) according to claim 1, characterized in that the output voltage generating circuit ( 23 . 24 . 25 ) one from a choke coil ( 24 ) and a capacitor ( 25 ) constructed smoothing circuit ( 24 . 25 ) and one parallel to the smoothing circuit ( 24 . 25 ) connected freewheel component ( 23 ) to return a current to the choke coil ( 24 ) contains if the switching component ( 29 ) is switched off, and the smoothing circuit ( 24 . 25 ) and the freewheel component ( 23 ) with the ground wiring structure ( 20 ) of the output voltage generating circuit ( 23 . 24 . 25 ) are connected. Electronic control device ( 1 ) according to claim 2, characterized in that the ground wiring structure ( 20 ) between the smoothing circuit ( 24 . 25 ) and the freewheeling component has an impedance that is smaller than that of the connecting part ( 23 ) is. Electronic control device ( 1 ) according to one of Claims 1 to 3, characterized in that the output voltage generating circuit ( 23 . 24 . 25 ) furthermore an input-side smoothing circuit ( 21 . 22 ), which is replaced by a choke coil ( 21 ) and a capacitor ( 22 ) is constructed, and contains a connection which is connected to the input connection of the switching component ( 29 ) is connected, the supply voltage to the input connection of the switching component after smoothing by the input-side smoothing circuit ( 21 . 22 ) is created, and the ground wiring structure ( 20 ) with another connection of the input-side smoothing circuit ( 21 . 22 ) connected is. Electronic control device ( 1 ) according to one of claims 1 to 4, characterized in that the ground wiring structure ( 20 ) in an upper layer of the multilayer substrate ( 15 ) is formed; and the connecting part ( 32 ) as an interlayer connection part for connecting the in the upper layer of the multilayer substrate ( 15 ) formed ground wiring structure ( 20 ) and that in an inner layer of the multilayer substrate ( 15 ) common ground wiring structure formed via an interlayer connection ( 30 ) is structured. Electronic control device ( 1 ) according to one of claims 1 to 4, characterized in that the ground wiring structure ( 20A ) in an inner layer of the multilayer substrate ( 15 ) is formed, which differs from the inner layer in which the common ground wiring structure ( 30 ) is formed; and the connecting part ( 32 ) as an interlayer connection part for connecting the ground wiring structure ( 20 ) with the common ground wiring structure ( 30 ) is structured via an interlayer connection. Electronic control device ( 1 ) according to one of claims 1 to 6, characterized in that the connecting part ( 32 ) has a contact hole through which the ground wiring structure ( 20 ) with the common ground wiring structure ( 30 ) connected is. Electronic control device ( 1 ) according to one of claims 1 to 6, characterized in that the connecting part ( 32 ) has a via, which has a conductive material on the inside, through which the ground wiring structure ( 20 ) with the common ground wiring structure ( 30 ) connected is. Electronic control device ( 1 ) according to claim 8, characterized in that the ground wiring structure ( 20 ) with the common ground wiring structure ( 30 ) via a ground connection of an electronic component inserted in the via ( 35 ) connected is.